Yamaha Fz1n Service Manual

OIL PUMP
5-63
EAS24970
CHECKING THE RELIEF VALVE
1. Check: Relief valve body “1”
Relief valve “2”
 Spring “3”
 O-ring “4”
Damage/wear  → Replace the defective 
part(s).
EAS24980
CHECKING THE OIL DELIVERY PIPES
1. Check:  Oil delivery pipe “1”
 Oil pipe “2”
Damage  → Replace.
Obstruction  → Wash and blow out with 
compressed air.
EAS24990
CHECKING THE OIL STRAINER
1. Check:  Oil strainer “1”
Damage  → Replace.
Contaminants  → Clean with solvent.
ET2D1013
CHECKING THE OIL NOZZLES
The following...

OIL PUMP
5-64
NOTE:
When installing the inner rotor, align the pin “1” 
in the oil pump shaft with the groove in the 
inner rotor “2”.
3. Install: Oil/water pump driven sprocket “1”
NOTE:
5VY mark of the oil/water pump driven gear is 
installed at oil pump side.
4. Check: Oil pump operation
Refer to CHECKING THE OIL PUMP on 
page 5-62.
EAS25030
INSTALLING THE OIL/WATER PUMP 
ASSEMBLY
1. Install:
 Oil ring 
 Oil/water pump assembly “1”
Dowel pin
 Bolts “2” 2. Install:
 Washer
 Oil/water pump...

OIL PUMP
5-65
4. Install: Oil delivery pipe “1”
5. Install: Relief valve “1”
 O-ring 
 Oil strainer “2”
 O-ring 
 Oil pipe “3”
 O-ring 
 Drain pipe “4”
 O-ring 
EAS25050
INSTALLING THE OIL PAN
1. Install: Dowel pins
Gasket 
 Oil pan “1”
 Oil level switch “2”
 Engine oil drain bolt “3”
WARNING
EWA12820
Always use new copper washers.
NOTE:
 Tighten the oil pan bolts in stages and in a 
crisscross pattern.
 Lubricate the oil level switch O-ring with 
engine oil.
Oil delivery pipe bolt
10 Nm...

CRANKCASE
5-66
EAS25540
CRANKCASE
Separating the crankcase
Order Job/Parts to remove Q’ty RemarksAir filter case Refer to GENERAL CHASSIS on  page 4-1.
Throttle body assembly Refer to THROTTLE BODIES on  page 7-4.
Engine Refer to ENGINE REMOVAL on  page 5-2.
Cylinder head Refer to CYLINDER HEAD on  page 5-19.
Generator Refer to GENERATOR on page 5- 31.
Starter clutch Refer to STARTER CLUTCH on  page 5-35.
Shift shaft Refer to SHIFT SHAFT on page 5- 54.
Crankshaft position sensor Refer to CRANKSHAFT...

CRANKCASE
5-67
Oil pump Refer to OIL PUMP on page 5-58.
Starter motor Refer to ELECTRIC STARTER on page 5-40.
1 Timing chain 1
2 Timing chain guide (intake side) 1
3Pin 2
4 Timing chain guide (exhaust side) 1
5 Left side cover 1
6O-ring 1
7 Lower crankcase 1
8 Dowel pin 3
9Damper 1 For assembly, reverse the removal 
procedure.
Separating the crankcase
Order Job/Parts to remove Q’ty Remarks 

CRANKCASE
5-68
EAS25550
DISASSEMBLING THE CRANKCASE
1. Place the engine upside down.
2. Remove: Crankcase bolts
NOTE:
 Loosen each bolt 1/4 of a turn at a time, in stages and in a crisscross pattern. After all of 
the bolts are fully loosened, remove them.
 Loosen the bolts in decreasing numerical  order (refer to the numbers in the illustration).
 The numbers embossed on the crankcase 
indicate the crankcase tightening sequence.
M9 x 105 mm (4.1 in) bolts: “1” – “10”
M8 x 60 mm (2.4 in) bolt: “11”...

CRANKCASE
5-69
3. Install: Dowel pin
4. Set the shift drum assembly and transmis- sion gears in the neutral position.
5. Install:  Lower crankcase “1”(onto the upper crankcase “2”)
CAUTION:
ECA13980
Before tightening the crankcase bolts, 
make sure the transmission gears shift cor-
rectly when the shift drum assembly is 
turned by hand.
6. Install:
 Crankcase bolts
NOTE:
 Lubricate the bolt threads with engine oil.
 Install a washer on bolts “1” – “10” and “22”.
 Seal bolt “18”
 Tighten the bolts...

CRANKSHAFT
5-70
EAS25950
CRANKSHAFT
Removing the connecting rods and pistons
Order Job/Parts to remove Q’ty RemarksLower crankcase Refer to CRANKCASE on page 5- 66.
1 Connecting rod cap 4
2 Big end lower bearing 4
3 Big end upper bearing 4
4 Piston pin clip 8
5 Piston pin 4
6Piston 4
7 Connecting rod 4
8Top ring 4
9 2nd ring 4
10 Oil ring 4
11 Cylinder 1
12 Cylinder gasket 1 For installation, reverse the removal 
procedure. 

CRANKSHAFT
5-71
Removing the crankshaft
Order Job/Parts to remove Q’ty RemarksCrankcase Separate. Refer to CRANKCASE on page 5-
66.
Connecting rod and connecting rod 
caps Refer to REMOVING THE CON-
NECTING RODS AND PISTONS 
on page 5-72.
1 Crankshaft 1
2 Crankshaft journal lower bearing 5
3 Crankshaft journal upper bearing 5
4 Washer 1
5 Crankshaft drive gear 1
6Pin 1
7Pickup rotor 1 For assembly, reverse the disassem-
bly procedure. 

CRANKSHAFT
5-72
EAS26030
REMOVING THE CONNECTING RODS AND 
PISTONS
The following procedure applies to all of the 
connecting rods and pistons.
1. Remove: Connecting rod cap “1”
 Big end bearings
NOTE:
 Idetify the position of each big end bearing 
so that it can be reinstalled in its original 
place.
 After removing the connecting rods and con- necting rod caps, care should be taken not to 
damage the mating surfaces of the connect-
ing rods and connecting rod caps.
2. Remove:  Cylinder
 Cylinder...